LAMW (solved) how to prevent location mocking / fake gps on LAMW

[Mongkey]

This is java article i've got, i knew it depreciated on API >25, but it very interesting.

https://www.programcreek.com/java-api-examples/?class=android.telephony.TelephonyManager&method=getAllCellInfo

Since i am very beginner on java, i cant implement it, because the return value like tstring.

[engkin]

I think this is a Pascal problem. Any Java object is simply translated as a pointer:

Code: Pascal  [Select][+][-]

1. unit And_jni;
2. ...
3. type
4. ....
5.      jobject=pointer;

including jList.

While, up to this point, it might be eaiser to solve problems on the Java side, I believe the proper way is to move the problem to the Pascal side.

[engkin]

For instance android.telephony.TelephonyManager is something like:

Code: Pascal  [Select][+][-]

1. unit uATTelephonyManager;
2.  
3. {$mode delphi}
4.  
5. interface
6.  
7. uses
8.   Classes, SysUtils, And_jni, AndroidWidget,
9.   Laz_And_Controls, uAndroidCommon;
10.  
11. type
12.  
13.   { jTelephonyManager }
14.  
15.   jTelephonyManager=class(jCommon)
16.   protected
17.     const CClassPath:string='android/telephony/TelephonyManager';
18.   protected
19.     {Shared by *all* jTelephonyManager instances}
20.     FjClass:jObject;static;
21.     FInitialized:boolean;static;
22.     //MethodId fields
23.     jMethodId_getPhoneCount:jmethodID;static;
24.     jMethodId_createForSubscriptionId:jmethodID;static;
25.     jMethodId_getDeviceSoftwareVersion:jmethodID;static;
26.     jMethodId_getDeviceId1:jmethodID;static;
27.     jMethodId_getDeviceId2:jmethodID;static;
28.     jMethodId_getCellLocation:jmethodID;static;
29.     jMethodId_getNeighboringCellInfo:jmethodID;static;
30.     jMethodId_getPhoneType:jmethodID;static;
31.     jMethodId_getNetworkOperatorName:jmethodID;static;
32.     jMethodId_getNetworkOperator:jmethodID;static;
33.     jMethodId_isNetworkRoaming:jmethodID;static;
34.     jMethodId_getNetworkCountryIso:jmethodID;static;
35.     jMethodId_getNetworkType:jmethodID;static;
36.     jMethodId_getDataNetworkType:jmethodID;static;
37.     jMethodId_getVoiceNetworkType:jmethodID;static;
38.     jMethodId_hasIccCard:jmethodID;static;
39.     jMethodId_getSimState:jmethodID;static;
40.     jMethodId_getSimOperator:jmethodID;static;
41.     jMethodId_getSimOperatorName:jmethodID;static;
42.     jMethodId_getSimCountryIso:jmethodID;static;
43.     jMethodId_getSimSerialNumber:jmethodID;static;
44.     jMethodId_getSubscriberId:jmethodID;static;
45.     jMethodId_getGroupIdLevel1:jmethodID;static;
46.     jMethodId_getLine1Number:jmethodID;static;
47.     jMethodId_setLine1NumberForDisplay:jmethodID;static;
48.     jMethodId_getVoiceMailNumber:jmethodID;static;
49.     jMethodId_setVoiceMailNumber:jmethodID;static;
50.     jMethodId_getVoiceMailAlphaTag:jmethodID;static;
51.     jMethodId_getCallState:jmethodID;static;
52.     jMethodId_getDataActivity:jmethodID;static;
53.     jMethodId_getDataState:jmethodID;static;
54.     jMethodId_listen:jmethodID;static;
55.     jMethodId_isVoiceCapable:jmethodID;static;
56.     jMethodId_isSmsCapable:jmethodID;static;
57.     jMethodId_getAllCellInfo:jmethodID;static;
58.     jMethodId_getMmsUserAgent:jmethodID;static;
59.     jMethodId_getMmsUAProfUrl:jmethodID;static;
60.     jMethodId_iccOpenLogicalChannel:jmethodID;static;
61.     jMethodId_iccCloseLogicalChannel:jmethodID;static;
62.     jMethodId_iccTransmitApduLogicalChannel:jmethodID;static;
63.     jMethodId_iccTransmitApduBasicChannel:jmethodID;static;
64.     jMethodId_iccExchangeSimIO:jmethodID;static;
65.     jMethodId_sendEnvelopeWithStatus:jmethodID;static;
66.     jMethodId_getIccAuthentication:jmethodID;static;
67.     jMethodId_setPreferredNetworkTypeToGlobal:jmethodID;static;
68.     jMethodId_hasCarrierPrivileges:jmethodID;static;
69.     jMethodId_setOperatorBrandOverride:jmethodID;static;
70.     jMethodId_canChangeDtmfToneLength:jmethodID;static;
71.     jMethodId_isWorldPhone:jmethodID;static;
72.     jMethodId_isTtyModeSupported:jmethodID;static;
73.     jMethodId_isHearingAidCompatibilitySupported:jmethodID;static;
74.     jMethodId_getVoicemailRingtoneUri:jmethodID;static;
75.     jMethodId_isVoicemailVibrationEnabled:jmethodID;static;
76.   protected
77.     class function get_jClass:jobject;override;
78.     class procedure get_jIDs;override;
79.   public
80.     constructor Create(AjObject:jObject=nil);overload;
81.     class procedure Init;
82.   public
83.     //Procs
84.     function getPhoneCount:jint;
85.     function createForSubscriptionId(_subId:jint):jobject;
86.     function getDeviceSoftwareVersion:String;
87.     function getDeviceId:String;overload;
88.     function getDeviceId(_slotId:jint):String;overload;
89.     function getCellLocation:jobject;
90.     function getNeighboringCellInfo:jobject;
91.     function getPhoneType:jint;
92.     function getNetworkOperatorName:String;
93.     function getNetworkOperator:String;
94.     function isNetworkRoaming:boolean;
95.     function getNetworkCountryIso:String;
96.     function getNetworkType:jint;
97.     function getDataNetworkType:jint;
98.     function getVoiceNetworkType:jint;
99.     function hasIccCard:boolean;
100.     function getSimState:jint;
101.     function getSimOperator:String;
102.     function getSimOperatorName:String;
103.     function getSimCountryIso:String;
104.     function getSimSerialNumber:String;
105.     function getSubscriberId:String;
106.     function getGroupIdLevel1:String;
107.     function getLine1Number:String;
108.     function setLine1NumberForDisplay(_alphaTag:String;_number:String):boolean;
109.     function getVoiceMailNumber:String;
110.     function setVoiceMailNumber(_alphaTag:String;_number:String):boolean;
111.     function getVoiceMailAlphaTag:String;
112.     function getCallState:jint;
113.     function getDataActivity:jint;
114.     function getDataState:jint;
115.     procedure listen(_listener:jobject;_events:jint);
116.     function isVoiceCapable:boolean;
117.     function isSmsCapable:boolean;
118.     function getAllCellInfo:jobject;
119.     function getMmsUserAgent:String;
120.     function getMmsUAProfUrl:String;
121.     function iccOpenLogicalChannel(_AID:String):jobject;
122.     function iccCloseLogicalChannel(_channel:jint):boolean;
123.     function iccTransmitApduLogicalChannel(_channel:jint;_cla:jint;_instruction:jint;_p1:jint;_p2:jint;_p3:jint;_data:String):String;
124.     function iccTransmitApduBasicChannel(_cla:jint;_instruction:jint;_p1:jint;_p2:jint;_p3:jint;_data:String):String;
125.     function iccExchangeSimIO(_fileID:jint;_command:jint;_p1:jint;_p2:jint;_p3:jint;_filePath:String):jbyte;
126.     function sendEnvelopeWithStatus(_content:String):String;
127.     function getIccAuthentication(_appType:jint;_authType:jint;_data:String):String;
128.     function setPreferredNetworkTypeToGlobal:boolean;
129.     function hasCarrierPrivileges:boolean;
130.     function setOperatorBrandOverride(_brand:String):boolean;
131.     function canChangeDtmfToneLength:boolean;
132.     function isWorldPhone:boolean;
133.     function isTtyModeSupported:boolean;
134.     function isHearingAidCompatibilitySupported:boolean;
135.     function getVoicemailRingtoneUri(_accountHandle:jobject):jobject;
136.     function isVoicemailVibrationEnabled(_accountHandle:jobject):boolean;
137.   end;
138.  
139. implementation
140.  
141. { jTelephonyManager }
142.  
143. constructor jTelephonyManager.Create(AjObject:jObject);
144. begin
145.   inherited Create(AjObject);
146. end;
147.  
148. ...
149. //code was removed to please the forum post limit :(
150.  

This code is machine generated. For now, it ignores exceptions which should be fixed.

You are interested in:

Code: Pascal  [Select][+][-]

1.     function getAllCellInfo:jobject;

Notice how it returns jobject. Now we need another class for java.util.List:

Code: Pascal  [Select][+][-]

1. unit uJUList;
2.  
3. {$mode delphi}
4.  
5. interface
6.  
7. uses
8.   Classes, SysUtils, And_jni, AndroidWidget,
9.   Laz_And_Controls, uAndroidCommon;
10.  
11. type
12.  
13.   { jList }
14.  
15.   jList=class(jCommon)
16.   protected
17.     const CClassPath:string='java/util/List';
18.   protected
19.     {Shared by *all* jList instances}
20.     FjClass:jObject;static;
21.     FInitialized:boolean;static;
22.     //MethodId fields
23.     jMethodId_size:jmethodID;static;
24.     jMethodId_isEmpty:jmethodID;static;
25.     jMethodId_contains:jmethodID;static;
26.     jMethodId_toArray1:jmethodID;static;
27.     jMethodId_toArray2:jmethodID;static;
28.     jMethodId_remove:jmethodID;static;
29.     jMethodId_addAll:jmethodID;static;
30.     jMethodId_removeAll:jmethodID;static;
31.     jMethodId_clear:jmethodID;static;
32.     jMethodId_equals:jmethodID;static;
33.     jMethodId_get:jmethodID;static;
34.     jMethodId_add:jmethodID;static;
35.     jMethodId_indexOf:jmethodID;static;
36.     jMethodId_listIterator1:jmethodID;static;
37.     jMethodId_listIterator2:jmethodID;static;
38.   protected
39.     class function get_jClass:jobject;override;
40.     class procedure get_jIDs;override;
41.   public
42.     constructor Create(AjObject:jObject=nil);overload;
43.     class procedure Init;
44.   public
45.     //Procs
46.     function size:jint;
47.     function isEmpty:boolean;
48.     function contains(__Param1:jobject):boolean;
49.     function toArray:jobject;overload;
50.     function toArray(__Param2:jobject):jobject;overload;
51.     function remove(__Param1:jobject):boolean;
52.     function addAll(__Param1:jobject):boolean;
53.     function removeAll(__Param1:jobject):boolean;
54.     procedure clear;
55.     function equals(__Param1:jobject):boolean;
56.     function get(__Param1:jint):jobject;
57.     procedure add(__Param1:jint;__Param2:jobject);
58.     function indexOf(__Param1:jobject):jint;
59.     function listIterator:jobject;overload;
60.     function listIterator(__Param1:jint):jobject;overload;
61.   end;
62.  
63. implementation
64.  
65. { jList }
66.  
67. constructor jList.Create(AjObject:jObject);
68. begin
69.   inherited Create(AjObject);
70. end;
71. ...
72. //code is cut to please the forum editor
73.  

Just like the previous code, this was machine generated.

In theory, you take the jobject from getAllCellInfo and pass it to jList.Create

jList should give you access to its items which are of type CellInfo, so we need a third class:

Code: Pascal  [Select][+][-]

1. unit uATCellInfo;
2.  
3. {$mode delphi}
4.  
5. interface
6.  
7. uses
8.   Classes, SysUtils, And_jni, AndroidWidget,
9.   Laz_And_Controls, uAndroidCommon;
10.  
11. type
12.  
13.   { jCellInfo }
14.  
15.   jCellInfo=class(jCommon)
16.   protected
17.     const CClassPath:string='android/telephony/CellInfo';
18.   protected
19.     {Shared by *all* jCellInfo instances}
20.     FjClass:jObject;static;
21.     FInitialized:boolean;static;
22.     //MethodId fields
23.     jMethodId_isRegistered:jmethodID;static;
24.     jMethodId_getTimeStamp:jmethodID;static;
25.     jMethodId_hashCode:jmethodID;static;
26.     jMethodId_equals:jmethodID;static;
27.     jMethodId_toString:jmethodID;static;
28.     jMethodId_describeContents:jmethodID;static;
29.     jMethodId_writeToParcel:jmethodID;static;
30.   protected
31.     class function get_jClass:jobject;override;
32.     class procedure get_jIDs;override;
33.   public
34.     constructor Create(AjObject:jObject=nil);overload;
35.     class procedure Init;
36.   public
37.     //Procs
38.     function isRegistered:boolean;
39.     function getTimeStamp:jlong;
40.     function hashCode:jint;
41.     function equals(_other:jobject):boolean;
42.     function toString:String;
43.     function describeContents:jint;
44.     procedure writeToParcel(__Param1:jobject;__Param2:jint);
45.   end;
46.  
47. implementation
48.  
49. { jCellInfo }
50.  
51. constructor jCellInfo.Create(AjObject:jObject);
52. begin
53.   inherited Create(AjObject);
54. end;
55.  
56. class procedure jCellInfo.Init;
57. var
58.   LjClass:jobject;
59. begin
60.   if not FInitialized then
61.   begin
62.     LjClass:=Get_jClassLocalRef(CClassPath);
63.     FjClass:=Get_jObjGlobalRef(LjClass);
64.     Delete_jLocalRef(LjClass);
65.     get_jIDs;
66.     FInitialized:=True;
67.   end;
68. end;
69.  
70. class function jCellInfo.get_jClass:jobject;
71. begin
72.   Result:=FjClass;
73. end;
74.  
75. class procedure jCellInfo.get_jIDs;
76. begin
77.   jMethodId_isRegistered:=Get_jMethodID(FjClass,'isRegistered','()Z');
78.   jMethodId_getTimeStamp:=Get_jMethodID(FjClass,'getTimeStamp','()J');
79.   jMethodId_hashCode:=Get_jMethodID(FjClass,'hashCode','()I');
80.   jMethodId_equals:=Get_jMethodID(FjClass,'equals','(Ljava/lang/Object;)Z');
81.   jMethodId_toString:=Get_jMethodID(FjClass,'toString','()Ljava/lang/String;');
82.   jMethodId_describeContents:=Get_jMethodID(FjClass,'describeContents','()I');
83.   jMethodId_writeToParcel:=Get_jMethodID(FjClass,'writeToParcel','(Landroid/os/Parcel;I)V');
84. end;
85.  
86. function jCellInfo.isRegistered:boolean;
87. begin
88. // ()Z
89.   Result:=jmethod_get_boolean(jMethodID_isRegistered);
90. end;
91.  
92. function jCellInfo.getTimeStamp:jlong;
93. begin
94. // ()J
95.   Result:=jmethod_get_jlong(jMethodID_getTimeStamp);
96. end;
97.  
98. function jCellInfo.hashCode:jint;
99. begin
100. // ()I
101.   Result:=jmethod_get_jint(jMethodID_hashCode);
102. end;
103.  
104. function jCellInfo.equals(_other:jobject):boolean;
105. var
106.   jParams:array[0..0] of jvalue absolute _other;
107. begin
108. // (Ljava/lang/Object;)Z
109.   Result:=jmethod_get_booleanA(jMethodId_equals,jParams);
110. end;
111.  
112. function jCellInfo.toString:String;
113. begin
114. // ()Ljava/lang/String;
115.   Result:=jmethod_get_String(jMethodID_toString);
116. end;
117.  
118. function jCellInfo.describeContents:jint;
119. begin
120. // ()I
121.   Result:=jmethod_get_jint(jMethodID_describeContents);
122. end;
123.  
124. procedure jCellInfo.writeToParcel(__Param1:jobject;__Param2:jint);
125. var
126.   jParams:array[0..1] of jvalue;
127. begin
128. // (Landroid/os/Parcel;I)V
129.   jParams[0].l:=__Param1;
130.   jParams[1].i:=__Param2;
131.   jmethod_voidA(jMethodId_writeToParcel,jParams);
132. end;
133.  
134. end.
135.  

It might be possible to use Pascal generics to make jList more like its counterpart in Java.

Anyway, I could be wrong, but this is how I see it.

WARNING:
This code was not tested.

[Mongkey]

 Thank you bro! I'll do my best to follow your sample.

[Mongkey]

i tried a lot, too much errors, not find symbol ,i dont understand java, its difficult for me  ,

I wish this attached code functions intact to LAMW jTelephony component, or new component jGeoFencing 

I got many fake gps coordinates, may be by retrieving from cell LAC, MNC solving this problem.

New candidate -> geofencing sample.

Thank you anyway!

[jmpessoa]

Done!

improved jTelephonyManager component

[need tests  and maybe some fix....]

[need "android.permission.ACCESS_COARSE_LOCATION"  granted by the user! ]

 GetLocationAreaCode()
 GetBaseStationId()
 GetMobileNetworkCode()
GetMobileCountryCode()

Thanks you!

PS. files changed:

"jTelephonyManager.java"
"telephonymanager.pas"

[Mongkey]

 ,

thanks prof JM, you are the best!

Actually i get more 1 solution for this:
for API > 18

Code: Java  [Select][+][-]

1. public static boolean isMockLocationOn(Context context) {
2.     if (Settings.Secure.getString(context.getContentResolver(), Settings.Secure.ALLOW_MOCK_LOCATION).equals("0"))
3.         return false;
4.     else
5.         return true;
6. }

[Mongkey]

Working very well on android 10, just tested get cell location, is it compatible for dual sim android? I gonna test it soon!

[Mongkey]

GetLocationAreaCode()
GetBaseStationId()
GetMobileNetworkCode()
GetMobileCountryCode()

After trying all, all retrieve same value (dual sim, sim1-> but with expiring telco subscription , no card on sim2), yesterday just tried GetLocationAreaCode(), not yet trying 3 others.

After inspecting -> working ok for dual sim -> detect on sim2 only, no card on sim1 -> WORK 

may be, retrieving same value if the card has expired -> useful for detecting no longer in service telco simcard 

[engkin]

This took me longer than I like. I kept having stange exception with an "invalid object". I tracked it down to a call in my code:

Code: Pascal  [Select][+][-]

1.   javContext:=gApp.GetContext();//<---- fails

which is:

Code: Pascal  [Select][+][-]

1. function jApp.GetContext(): jObject;
2. begin
3.   Result:= jApp_GetContext(Self.Jni.jEnv, Self.Jni.jThis);//<--- this fails!!
4. end;

I assumed Self.Jni.jThis is not holding a valid value anymore, so I turned it into a Java global variable reference:

Code: Pascal  [Select][+][-]

1. var
2.   gThis:jobject;
3.   gContext:jobject;
4.  
5. procedure Java_Event_pAppOnCreate(env: PJNIEnv; this: jobject; context:jobject; layout:jobject; intent: jobject);
6. begin
7.   gThis:=env^.NewGlobalRef(env,this);
8.   gContext:=env^.NewGlobalRef(env,context);
9.  
10.   gApp.IsAppActivityRecreate := gApp.FInitialized;
11.   gApp.FInitialized := False;
12.   //gApp.Init(env,this,context,layout, intent);
13.   gApp.Init(env,gThis,gContext,layout, intent);
14. end;

Surprisingly that was not enough!!
then I skipped Self.Jni.jThis and used the global variable gThis directly:

Code: Pascal  [Select][+][-]

1. function jApp.GetContext(): jObject;
2. begin
3.   Result:= jApp_GetContext(Self.Jni.jEnv, gThis);
4. end;

Now it works:

<Init>
</Init>
<Context>
gApp.APILevel: 30
prob: 7
</Context>
<Activity>
</Activity>
pasContext.TELEPHONY_SERVICE:
phone
<TelephonyManager>
<getAllCellInfo>
<List>
pasList.size: 4
<Loop>
get(0)
CellInfo
CellInfoLte:{mRegistered=YES ....
get(1)
CellInfo
CellInfoLte:{mRegistered=NO ...
get(2)
CellInfo
CellInfoLte:{mRegistered=NO ...
get(3)
CellInfo
CellInfoLte:{mRegistered=NO ...
</Loop>

[jmpessoa]

function jApp.GetContext(): jObject;
begin
  Result:= jApp_GetContext(Self.Jni.jEnv, Self.Jni.jThis);//<--- this fails!!
end;

You can see in "Laz_And_Controls_Events.pas"  and "Laz_And_Controls.pas"

that all  "Java_Event_*"  call has some code like this:

Code: [Select]

Procedure Java_Event_pOnTimePicker(env: PJNIEnv; this: jobject; Obj: TObject; hourOfDay: integer; minute: integer);
begin

  gApp.Jni.jEnv := env;          // <----
  if this <> nil then gApp.Jni.jThis := this;      // <----

  ......
  .......
end; 

It keeps these global data always "up to date"!

the reference is here:

https://android-developers.googleblog.com/2011/11/jni-local-reference-changes-in-ics.html


Are you "by passing" LAMW code architecture?

[engkin]

No, I am not bypassing LAMW's architecture. I am trying to extend it by bringing Java/Android classes to Pascal.

As your reference link shows, Java_Event_pAppOnCreate is expected to use env->NewGlobalRef to store its parameters on the Pascal side, otherwise these values become invalid because of the Garbage Collector moving them around. How come you're not following that reference? 

I made a simple app with a jButton and jEditText. The button calls javContext:=gApp.GetContext();

That call fails because gApp.Jni.jThis became invalid.
Then I used NewGlobalRef as soon as I received the parameters in Java_Event_pAppOnCreate
Passing the results to jApp.Init *seemed* not to work,
but NOW, thanks to your explanation, I think they got overwritten by LOCAL references again.

That explains why it worked when I used gThis directly,  because it holds the GLOBAL reference.

If my understanding is correct, there is a bug in LAMW, it should set the members of jApp.Jni once, AND it should use NewGlobalRef for that, AND it should not change them inside Java_Event_* in unit "Laz_And_Controls_Events.pas"  or any other place.

Of course, at the end of the app it should delete the global references.

[jmpessoa]

So at the moment we are doing different readings of the document.....

this code:

Code: Pascal  [Select][+][-]

1. Procedure Java_Event_pOnTimePicker(env: PJNIEnv; this: jobject; Obj: TObject; hourOfDay: integer; minute: integer);
2. begin
3.  
4.   gApp.Jni.jEnv := env;          // <----
5.   if this <> nil then gApp.Jni.jThis := this;      // <----
6.  
7.   ......
8.   .......
9. end;
10.  

is vital for the entire LAMW code architecture ... and yes "gApp" is global, but  properties
gApp.Jni.jEnv and  gApp.Jni.jThis  need to be continually updated
otherwise we will get "staled"  object reference....

[engkin]

When I said global, I was not talking about Pascal global variables.  I meant Jave global references. These references do not stall, the Garbage Collector doesn't touch them.

What you receive in Java_Event_* is Java local references, these local references will stall. If you intend to use them outside these procedures, as in LAMW, you're supposed to turn the Java local references to Java global references.

This is what the article you linked is saying, and it is what works on my side.

If you are not convinced, can you show me one simple example where my suggestion will not work?

[jmpessoa]

can you show me one simple example where my suggestion .....

From reference:

Now there’s a per-thread local reference table, it’s vital that you only use a JNIEnv* on the right thread.

If you have a native peer (a long-lived native object corresponding to a Java object, usually created when the Java object is created and destroyed when the Java object’s finalizer runs), you must not stash a jobject in that native object, because it won’t be valid next time you try to use it. (Similar is true of JNIEnv*s. They might be valid if the next native call happens on the same thread, but they won’t be valid otherwise.)

and from here: https://developer.android.com/training/articles/perf-jni

The JNIEnv is used for thread-local storage. For this reason, you cannot share a JNIEnv between threads.

Remember that "LAMW Pascal" side/code  talk to "LAMW java" [multi-thread?] side/code..... 

So at some time if you comment out these two lines of code:

  gApp.Jni.jEnv := env;                             // <----
  if this <> nil then gApp.Jni.jThis := this;  // <--- 

you will get  a staled object reference .....